1. Technical Field
The present invention relates to an optical transceiver, in particular a structure to connect an optical transceiver to a host substrate.
2. Description of Related Art
Optical transceivers in which optical modules to reciprocally convert electrical signals and optical signals are packaged have been known. For optical transceivers, there are standards such as Small Form-factor Pluggable (SFP) transceivers and 10 Gbit/s small Form-factor Pluggable (XFP) transceivers. Such an optical transceiver is connected to a host substrate of an optical communication device (a switch, a router, and the like) through a connector mounted on that host substrate. As communication capacity has increased, it is necessary to implement a plurality of channels in a single host substrate in an optical communication device. Therefore, in an optical transceiver implementing channels, it has been desired to reduce the area on the host substrate where the optical transceiver is mounted.
Japanese Unexamined Patent Application Publication No. 2006-229067 discloses an optical transceiver including a connection terminal extending lengthwise and crosswise. With providing the connection terminal extending lengthwise and crosswise, it is possible to miniaturize the optical module in comparison to the case where all connection terminals are formed on one side of an optical module. In this way, it is possible to reduce the mounting area on the host substrate. Furthermore, Japanese Unexamined Patent Application Publication No. H08-203629 discloses, though it is not for optical transceivers, a structure to connect a printed-circuit board to a host substrate in such a manner that the printed-circuit board is perpendicular to the host substrate. By connecting the printed-circuit board perpendicularly to the host substrate, it is possible to reduce the mounting area for the printed-circuit board on the host substrate.
However, there is a problem in the optical transceiver described in Japanese Unexamined Patent Application Publication No. 2006-229067 that since the printed-circuit board on which the optical module is mounted is connected to the host substrate such that the printed-circuit board is horizontal with respect to the host substrate, the mounting area on the host substrate is large. Meanwhile, since the printed-circuit board is fixed to the host substrate with solder in the connection structure of the printed-circuit board described in Japanese Unexamined Patent Application Publication No. H08-203629, it is not suitable for the usage of optical transceivers. Because the optical transceivers are often removed and inserted again when a malfunction occurs in an optical communication device and a new application device is additionally mounted to the host substrate.